They did, yes. But that stopped being viable after the beginning of the industrial revolution when our population growth far surpassed the amount of gold available. The price of gold per gram right now is $106.68, and the price of silver per ounce is $36.84. Makes it hard to buy coffee or make change with those.

The printing of paper currency is a fraction of the total circulating supply. The bulk of fiat is in debt instruments. Can't really buy coffee with those either. With Bitcoin you can handle transactions of any size.

Humanity has been at peace for a very small fraction of the time over the last few thousand years. Fighting seems to be all we really know how to do.